Ground-layer turbulence evaluation project at Subaru Telescope

A candidate of the next-generation adaptive optics (AO) system at Subaru Telescope is a ground-layer AO (GLAO) using an adaptive secondary mirror. The performance of GLAO depends on the turbulence profile because only ground-layer turbulence is corrected. At Mouna Kea, the profile data have been obtained at the summit ridge site and TMT site. However, the height difference of the Subaru site from these sites is about 100 m, close to the scale height of the ground-layer turbulence. There is a possibility that the topographical difference affects the ground-layer turbulence property, and then the performance of GLAO. In this paper, the activity to evaluate the ground-layer turbulence at the Subaru site is introduced.